Although the Sindarin word for 'orcs' is 'yrch',this rare but more descriptive term is also sometimes seen (although not in The Lord of the Rings or The Silmarillion).'Glamhoth' does appear,however,in Tuor's curse in the unfinished Of Tuor and His Coming to Gondolin1;"Gurth an glamhoth" - 'death to the orcs'.It is also probably seen in a shortened form in the name of Gandalf's sword,Glamdring.
Goblins :
A name for Orcs and especially the smaller kinds that infested the Misty and the Grey Mountains in the later Third Age and had their capital at Mount Gundabad.
Orcs :
Little is known for certain of the beginnings of the Orcs,the footsoldiers of the Enemy.It is said that they were in origin corrupted Elves captured by Melkor before the beginning of the First Age.In appearance,Orcs were squat,swarthy creatures.Most of them preferred the darkness,being blinded by the light of the Sun but the kinds bred later in the Third Age such as the Uruk-hai could endure the daylight.
Yrch :
The Sindarin name for the race known to Men as Orcs.'Yrch' is the plural form; the singular is 'orch'.
